Winter's coming. Won't ride as much. What do you F800ST owners do when long down times arrive? I have a pigtail hooked to the battery. Can I use a 12v battery trickle charger...or do I need to buy a BMW Can Bus unit?
Can you leave a bike on the charger for long periods?
Use the pigtail and a bona-fide Battery Tender. I used it on the F800S, and now use it on the R1200S. It works.
I have the BMW Advanced Battery Charging System hooked up to my F800st. It works pretty good...nothing special. I was told its best to have a trickle charger/battery tender on the bike because it knows when to shut down and won't cook your battery. The BMW tender has 2 settings....storage and charging. I also have a Sears/Craftsman motorcycle tender/charger for my GPZ 550 and it works good too.
You can go exotic and buy a VW solar panel from ebay for short money, wire it to the battery and use the sun to keep the battery topped off. VW uses these when they ship cars. They often sit in parking lots at ports of entry for extended periods -- keeps the batteries from going to zero volts.
I bought a few of them maybe 4 years ago. They work. Wire it directly to the battery to avoid that cannibus thing...
These work via canbus and are cheaper than the BMW version.
battery tendr Jr. much less expensive...and works on lead acid and gel glassmat.